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 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package javax.swing.table;

import javax.swing.*;
import javax.swing.event.*;
import java.io.Serializable;
import java.util.EventListener;

/**
 * This abstract class provides default implementations for most of
 * the methods in the <code>TableModel</code> interface. It takes care of
 * the management of listeners and provides some conveniences for generating
 * <code>TableModelEvents</code> and dispatching them to the listeners.
 * To create a concrete <code>TableModel</code> as a subclass of
 * <code>AbstractTableModel</code> you need only provide implementations
 * for the following three methods:
 *
 * <pre>
 *  public int getRowCount();
 *  public int getColumnCount();
 *  public Object getValueAt(int row, int column);
 *  </pre>
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Alan Chung
 * @author Philip Milne
 */
public abstract class AbstractTableModel implements TableModel, Serializable {
//
// Instance Variables
//

  /**
   * List of listeners
   */
  protected EventListenerList listenerList = new EventListenerList();

//
// Default Implementation of the Interface
//

  /**
   * Returns a default name for the column using spreadsheet conventions:
   * A, B, C, ... Z, AA, AB, etc.  If <code>column</code> cannot be found,
   * returns an empty string.
   *
   * @param column the column being queried
   * @return a string containing the default name of <code>column</code>
   */
  public String getColumnName(int column) {
    String result = "";
    for (; column >= 0; column = column / 26 - 1) {
      result = (char) ((char) (column % 26) + 'A') + result;
    }
    return result;
  }

  /**
   * Returns a column given its name.
   * Implementation is naive so this should be overridden if
   * this method is to be called often. This method is not
   * in the <code>TableModel</code> interface and is not used by the
   * <code>JTable</code>.
   *
   * @param columnName string containing name of column to be located
   * @return the column with <code>columnName</code>, or -1 if not found
   */
  public int findColumn(String columnName) {
    for (int i = 0; i < getColumnCount(); i++) {
      if (columnName.equals(getColumnName(i))) {
        return i;
      }
    }
    return -1;
  }

  /**
   * Returns <code>Object.class</code> regardless of <code>columnIndex</code>.
   *
   * @param columnIndex the column being queried
   * @return the Object.class
   */
  public Class<?> getColumnClass(int columnIndex) {
    return Object.class;
  }

  /**
   * Returns false.  This is the default implementation for all cells.
   *
   * @param rowIndex the row being queried
   * @param columnIndex the column being queried
   * @return false
   */
  public boolean isCellEditable(int rowIndex, int columnIndex) {
    return false;
  }

  /**
   * This empty implementation is provided so users don't have to implement
   * this method if their data model is not editable.
   *
   * @param aValue value to assign to cell
   * @param rowIndex row of cell
   * @param columnIndex column of cell
   */
  public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
  }

//
//  Managing Listeners
//

  /**
   * Adds a listener to the list that's notified each time a change
   * to the data model occurs.
   *
   * @param l the TableModelListener
   */
  public void addTableModelListener(TableModelListener l) {
    listenerList.add(TableModelListener.class, l);
  }

  /**
   * Removes a listener from the list that's notified each time a
   * change to the data model occurs.
   *
   * @param l the TableModelListener
   */
  public void removeTableModelListener(TableModelListener l) {
    listenerList.remove(TableModelListener.class, l);
  }

  /**
   * Returns an array of all the table model listeners
   * registered on this model.
   *
   * @return all of this model's <code>TableModelListener</code>s or an empty array if no table
   * model listeners are currently registered
   * @see #addTableModelListener
   * @see #removeTableModelListener
   * @since 1.4
   */
  public TableModelListener[] getTableModelListeners() {
    return listenerList.getListeners(TableModelListener.class);
  }

//
//  Fire methods
//

  /**
   * Notifies all listeners that all cell values in the table's
   * rows may have changed. The number of rows may also have changed
   * and the <code>JTable</code> should redraw the
   * table from scratch. The structure of the table (as in the order of the
   * columns) is assumed to be the same.
   *
   * @see TableModelEvent
   * @see EventListenerList
   * @see javax.swing.JTable#tableChanged(TableModelEvent)
   */
  public void fireTableDataChanged() {
    fireTableChanged(new TableModelEvent(this));
  }

  /**
   * Notifies all listeners that the table's structure has changed.
   * The number of columns in the table, and the names and types of
   * the new columns may be different from the previous state.
   * If the <code>JTable</code> receives this event and its
   * <code>autoCreateColumnsFromModel</code>
   * flag is set it discards any table columns that it had and reallocates
   * default columns in the order they appear in the model. This is the
   * same as calling <code>setModel(TableModel)</code> on the
   * <code>JTable</code>.
   *
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableStructureChanged() {
    fireTableChanged(new TableModelEvent(this, TableModelEvent.HEADER_ROW));
  }

  /**
   * Notifies all listeners that rows in the range
   * <code>[firstRow, lastRow]</code>, inclusive, have been inserted.
   *
   * @param firstRow the first row
   * @param lastRow the last row
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableRowsInserted(int firstRow, int lastRow) {
    fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
        TableModelEvent.ALL_COLUMNS, TableModelEvent.INSERT));
  }

  /**
   * Notifies all listeners that rows in the range
   * <code>[firstRow, lastRow]</code>, inclusive, have been updated.
   *
   * @param firstRow the first row
   * @param lastRow the last row
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableRowsUpdated(int firstRow, int lastRow) {
    fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
        TableModelEvent.ALL_COLUMNS, TableModelEvent.UPDATE));
  }

  /**
   * Notifies all listeners that rows in the range
   * <code>[firstRow, lastRow]</code>, inclusive, have been deleted.
   *
   * @param firstRow the first row
   * @param lastRow the last row
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableRowsDeleted(int firstRow, int lastRow) {
    fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
        TableModelEvent.ALL_COLUMNS, TableModelEvent.DELETE));
  }

  /**
   * Notifies all listeners that the value of the cell at
   * <code>[row, column]</code> has been updated.
   *
   * @param row row of cell which has been updated
   * @param column column of cell which has been updated
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableCellUpdated(int row, int column) {
    fireTableChanged(new TableModelEvent(this, row, row, column));
  }

  /**
   * Forwards the given notification event to all
   * <code>TableModelListeners</code> that registered
   * themselves as listeners for this table model.
   *
   * @param e the event to be forwarded
   * @see #addTableModelListener
   * @see TableModelEvent
   * @see EventListenerList
   */
  public void fireTableChanged(TableModelEvent e) {
    // Guaranteed to return a non-null array
    Object[] listeners = listenerList.getListenerList();
    // Process the listeners last to first, notifying
    // those that are interested in this event
    for (int i = listeners.length - 2; i >= 0; i -= 2) {
      if (listeners[i] == TableModelListener.class) {
        ((TableModelListener) listeners[i + 1]).tableChanged(e);
      }
    }
  }

  /**
   * Returns an array of all the objects currently registered as <code><em>Foo</em>Listener</code>s
   * upon this <code>AbstractTableModel</code>. <code><em>Foo</em>Listener</code>s are registered
   * using the <code>add<em>Foo</em>Listener</code> method.
   *
   * <p>
   *
   * You can specify the <code>listenerType</code> argument with a class literal, such as
   * <code><em>Foo</em>Listener.class</code>. For example, you can query a model <code>m</code> for
   * its table model listeners with the following code:
   *
   * <pre>TableModelListener[] tmls = (TableModelListener[])(m.getListeners(TableModelListener.class));</pre>
   *
   * If no such listeners exist, this method returns an empty array.
   *
   * @param listenerType the type of listeners requested; this parameter should specify an interface
   * that descends from <code>java.util.EventListener</code>
   * @return an array of all objects registered as <code><em>Foo</em>Listener</code>s on this
   * component, or an empty array if no such listeners have been added
   * @throws ClassCastException if <code>listenerType</code> doesn't specify a class or interface
   * that implements <code>java.util.EventListener</code>
   * @see #getTableModelListeners
   * @since 1.3
   */
  public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
    return listenerList.getListeners(listenerType);
  }
} // End of class AbstractTableModel
